I might be able to offer some informartion on this.
I've got a panasonic PX60, I notice that even with the expanded VGA settings the image, although sharper definately looks more flat and lifeless than over component.
This is comparing 1360x768 for VGA against, 720p and 1080i
1080i looks best for HDDVDs and some games, but you get some motion blurring (invisible in films, but noticeable in games like PES6 which has a high contrast of the players on the green pitch) as opposed to 720p which is a little softer.
I personally chose 1080i every time.
This is in compete contrast to a plasma I owned last summer where the VGA connection looked far superior.
Basically as already said, if your screen can do VGA justice, then VGA will usually look better, it will almost always look crispier either way. But if your screen isn't too good on the VGA input then depending on your preferences and biasedness on interlaced\progressive signals.....720p\1080i....
I think all that translates to is...Unless you know someone on the forum with same setup who has already looked for best connection\settings....its trial and error all the way
(Its also very important to calibrate your display on VGA, more so than component, my panasonic looks almost like VHS until i'd had a good hours fiddling with the contrast\etc....still could never get a juicy pic...but there we go eh

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